It is mostly used in maintenance department.
The maintenance engineer inspects the plant periodically under working condition and when it is rest, with good planning and preparation.
The planning of maintenance is categorized in following ways-
- Routine maintenance
- Periodically maintenance
- Maintenance of fault when fault occurs
It should be carried out daily.
It includes visual inspection, minor repairs such as replacement of small parts and adjustment of equipment for operation.
Routine maintenance includes cleaning of electrical equipment from dust and dirt, cleaning of the fitting, tank cover, cleaning of fixed and movable contacts of starters, replacement of burnt contacts.
It also involves washing a lubricant of bearing, checking of control equipment and replacement of carbon process etc.
It is carried out without dismantling the equipment.
Supply must be disconnected before any repair undertaken.
It is carried out weekly, fortnightly, quarterly, or healthy depending upon the condition and requirement of the machine.
It includes inspection of loose parts, ventilation, replacement of whorl parts, change of oil, checking of insulation.
Maintenance on fault-
It is carried out immediately when a fault occurs.
It is carried out half yearly or yearly.
It consists of replacement of the main unit, assemblies and parts of electrical equipment.
It involves such work like rewinding of motor, starter, replacement of bushing of the high voltage circuit breaker are involves partial or complete dis metal of equipment.